San José de Guaviare Syenite, Colombia: Repeated Ediacaran intrusions in the northwestern Amazonian Craton
| Autor: | Mario Maya Sánchez, Orlando Manuel Pérez Parra, Nilson Francisquini Botelho, Carolina Amaya López, Mauricio Ibañez Mejía, Jorge Julián Restrepo Álvarez, Federico Alberto Cuadros Jiménez, Carlos Ramírez Cárdenas, Marion Weber Scharff |
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| Jazyk: | angličtina |
| Rok vydání: | 2021 |
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| Zdroj: | Boletín Geológico, Vol 48, Iss 1, Pp 49-79 (2021) |
| ISSN: | 2711-1318 0120-1425 |
| Popis: | The Neoproterozoic igneous rocks found in the municipality of San José del Guaviare include several isolated plutonic bodies that protrude from the Phanerozoic sedimentary cover in belts aligned NW-SE. Limited to the Guaviare department, these intrusions stretch from the La Lindosa mountain range to the corregimiento El Capricho. These plutonic bodies consist of nepheline syenites, nepheline monzosyenites, nepheline-bearing alkali-feldspar syenites, syenites, quartz-syenites, quartz-alkali-feldspar syenites, syenogranites, and quartz-rich granitoids, which have been grouped and termed the San José del Guaviare Syenite unit (SJGS). The intrusion of the unit occurred in the Ediacaran (604 ± 7 Ma and 620.5 ± 7.5 Ma) by mantle-derived alkaline magmas formed in anorogenic settings, most likely in rift-like stretching zones. The silica-subsaturated magma may have reacted with host rocks at the crust level, producing some silica-saturated igneous rocks, such as syenogranites and quartz-syenites, which are found in the El Capricho and Cerritos bodies. |
| Databáze: | OpenAIRE |
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